Pressure adjustable foam support apparatus

ABSTRACT

A pressure adjustable foam support apparatus includes a resilient, air pressure adjustable, self-inflating foam core. A flexible, airtight cover encloses the core. An air passageway in formed through the covering in pneumatic communication with the foam core. The passageway carries a valve for alternately permitting and blocking passage into and out of the core through the passageway. The valve is opened to exhaust air from and at least partially collapse the core and to allow a core that is at least partially collapsed to draw in air through the passageway and expand. The valve is closed to maintain a selected air pressure within the core whereby corresponding levels of density and firmness are exhibited by the core. At least one level of density and firmness provides the core with a viscoelastic feel.

RELATED APPLICATION

[0001] This application is a continuation in part U.S. patent application Ser. No. 09/800,752 filed Mar. 7, 2001.

FIELD OF THE INVENTION

[0002] This invention relates to a pressure adjustable foam support apparatus and to a method of producing a body supporting structure with adjustable levels of density and firmness simulating those of viscoelastic foam.

BACKGROUND OF THE INVENTION

[0003] Recently, high density viscoelastic foam has been used in mattresses and support pads. This material, which was originally developed for NASA, exhibits a slow recovery time after an external pressure is applied to it. Viscoelastic foam products are intended to conform with the contours of the user's body and provide improved comfort and support. Unfortunately, conventional viscoelastic foam presents a number of disadvantages. Due to its high density (typically in excess of 3 lbs/ft³), this material is quite bulky and heavy. A standard viscoelastic pad typically weighs approximately six times as much as a comparably sized polyurethane foam pad. This makes the high density foam quite difficult and inconvenient to handle and maneuver. The viscoelastic product is also extremely expensive. Furthermore, conventional viscoelastic foam is not pressure adjustable to meet the individual user's needs.

[0004] Various self-inflating and pressure adjustable foam mattresses have been developed. See for example, Lea et al., U.S. Pat. No. 3,872,525, Nissen, U.S. Pat. No. 5,023,133, Bridgens, U.K. Patent No. 984,604 and my previous U.S. Pat. No. 6,038,722. To date, these devices have been particularly designed for outdoor and recreational use. None of the self-inflating mattresses or cushions are suitable for use as a conventional bedroom mattress. For example, the Lea product is very thin and employed primarily as a camping mat. It is difficult to successfully adjust the pressure in the Lea mattress or to provide for desired levels of comfort because of the relative thinness of the item. If a user is lays upon the Lea mattress with the valve open, the foam cushion fully deflates almost immediately. It is very difficult, if not impossible, to adjust the pressure and comfort level in either this or the other known products. In fact, to date, selfinflating polyurethane foam mattresses have been utilized in only a fully inflated or fully deflated condition. Intermediate air pressure adjustment has not been exhibited in any of these devices.

[0005] There is a good reason that pressure adjustability has not been a factor to date in the design of self-inflating foam filled mattresses. Pressure adjustability is most important for mats, mattresses and pads that are designed for indoor use (e.g. beds, sofas, furniture, etc.). Such support structures are usually relatively thick in order to provide the needed support and comfort levels desired by most persons. Inflating and deflating a thick foam pad according to the teachings of the above cited prior art would require considerable time and effort and hence has made the use of self-inflating foam to date impractical for indoor use. Persons desiring custom pressure adjustment have been limited to the use of air bladder mattresses. These types of structures do not employ foam and do not provide the support, comfort and conformance with the body that is provided by viscoelastic pads. As stated, however, the viscoelastic products exhibit a number of disadvantages and limitations. Moreover, it would be impractical to make such foam collapsible or pressure adjustable. Due to its high density and tight cellular structure, the typical viscoelastic foam mattress has poor air flow. Collapsing and storing the product would require considerable time and effort.

SUMMARY OF INVENTION

[0006] It is therefore an object of the present invention to provide a foam support apparatus that is conveniently pressure adjustable to achieve comfort and support qualities comparable to those of a viscoelastic product.

[0007] It is a further object of this invention to provide a pressure adjustable foam support apparatus utilizing a low density foam which functions comparably to viscoelastic foam, but which is much less expensive, much lighter weight and far easier to handle than any viscoelastic support surface, or any other normal box spring mattress.

[0008] It is a further object of this invention to provide a foam support apparatus that is quickly and conveniently pressure adjusted to provide desired levels of density and firmness so that the user's individual comfort and support needs may be met.

[0009] It is a further object of this invention to provide a pressure adjustable foam support apparatus which may be partially or fully deflated and collapsed in a quick and convenient manner by a single person using very little time, effort and exertion.

[0010] It is a further object of this invention to provide a pressure adjustable foam support apparatus that is quick, convenient and virtually effortless to assemble and disassemble.

[0011] It is a further object of this invention to provide a pressure adjustable foam support apparatus that operates relatively smoothly and effortlessly.

[0012] This invention results from a realization that a relatively low density self-inflating foam may be pressure adjusted so that it exhibits a density and firmness comparable to a much more expensive, heavier and non-adjustable viscoelastic foam product. In particular, air is exhausted from the low density foam such that the cellular structure of the foam is modified. This increases the density and reduces the indention force deflection (IFD) of the self-inflating foam such that these values are equivalent and provide a feel similar to those of a non-adjustable viscoelastic foam product. A much less expensive and yet lightweight and easier to handle product is thereby achieved. Nonetheless, the adjustable foam product exhibits advantages and qualities which are comparable to those of the viscoelastic product.

[0013] This invention features a pressure adjustable foam support apparatus including a resilient, air pressure adjustable, self-inflating foam core and a flexible, airtight cover that encloses the core. An air passageway is formed through the covering in pneumatic communication with the foam core. The passageway carries a valve for alternately permitting and blocking passage of air into and out of the core through the passageway. The valve is opened to exhaust air from and at least partially collapse the core and to allow a core that is at least partially collapsed to draw in air through the passageway and expand. The valve is closed to maintain a selected air pressure within the core whereby corresponding levels of density and firmness are exhibited by the core.

[0014] In a preferred embodiment, the apparatus further includes a vacuum pump communicably engagable with the passageway such that opening the valve and operating the pump exhausts air from the foam core through the passageway to at least partially collapse the core. The passageway may include a first pipe portion disposed within the covering and a second pipe portion attached communicably to and extending transversely to the first pipe portion. The second pipe portion may extend through and be pneumatically communicable with air exteriorly of the covering. A baffle may be disposed adjacent to the passageway and intermediate the foam core and the cover to restrict the cover from being sucked into the passageway by operation of the vacuum pump. A foam core may include at least two innerengaged foam components disposed within the covering. Each foam component may include a respective density and indention force deflection (IFD) that is different from that of the other foam core. The vacuum pump may be attached to the passageway exteriorly of the covering. Alternatively, the vacuum pump may be attached to the passageway interiorly of the covering.

[0015] Preferably, the foam core includes a polyurethane foam. The core may have a density of 1.2-2.5 pounds per cubic foot and an indention force deflection of 22 to 45 in a full inflated condition. Preferably, the core is collapsible to a degree such that it includes a density of at least 3 lbs/ft³ and an indention force deflection of less than 15. The core may include a normal cellular structure in a fully inflated condition and a modified cellular structure in the partially collapsed condition, which modified cellular structure is caused by a reduction in air pressure in the foam cells. The foam core may include at least two interengaged foam components disposed within the cover. Each foam component may include a respective density and indention force deflection that is different from that of the other foam component.

[0016] This invention also features a method of producing a pressure adjustable foam support apparatus which includes selected levels of density and firmness. The method includes providing a resilient, air pressure adjustable, self-inflating foam core and enclosing the foam core in a flexible airtight covering. An air passage is provided through the covering in pneumatic communication with the foam core. The passageway carries a valve for alternately permitting or blocking the passage of air into and out of the core through the passageway. The valve is opened to selectively exhaust air from and introduced air into the core through the passageway to adjust the pressure within the core until the core achieves selected levels of density and firmness. The valve is then closed to maintain the core at the selected levels of density and firmness.

[0017] Preferably, the air is exhausted from the core by opening the valve and pumping air from the core outwardly through the passageway. This modifies the cellular structure of the core. The foam core may initially include a density of 1.2-2.5 pounds per cubic foot and an IDF of 22-45 in a fully inflated condition. The core is partially collapsed by a vacuum pump engaged with the passageway until a density of at least 3 lbs/ft³ and an IDF of below 15 is achieved. As a result, the low density foam core simulates the feel of a high density viscoelastic foam component.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0018] Other objects, features and advantages will occur from the following description of preferred embodiments and the accompanying drawings, in which:

[0019]FIG. 1 is a perspective, partly schematic view of a pressure adjustable foam support apparatus according to this invention;

[0020]FIG. 2 is a perspective, partly cut away view of the air passageway, baffle and foam core of the support apparatus;

[0021]FIG. 3 is an elevational, cross sectional view of the support apparatus and in particular, the foam core, air passageway and an airtight covering;

[0022]FIG. 4 is an elevational view of a person laying upon the support apparatus;

[0023]FIG. 5 is a perspective; partly exploded view of an alternative preferred air passageway and valve;

[0024]FIG. 6 is an elevational view of the foam core, air passageway and valve shown in FIG. 5;

[0025]FIG. 7 is a top, partially cross sectional view of the adjustable support apparatus with an external vacuum attached to the air passageway;

[0026]FIG. 8 is a partial plan view of the support structure including a vacuum carried by the support component and permanently and communicably connected to the air passageway;

[0027]FIG. 9 is a view similar to FIG. 6 but with a vacuum pump attached to the mat and releasably interengaged with the air passageway;

[0028]FIG. 10 is a top cross sectional view of the apparatus shown in FIG. 9; and

[0029]FIG. 11 is a view similar to FIG. 10 but of an alternative embodiment wherein the vacuum pump is disposed internally within the covering of the support component.

[0030] There is shown in FIG. 1 a pressure adjustable foam support apparatus 10 comprising a body supporting component 12 that is releasably and adjustably interengaged with a conventional vacuum pump 13. Body supporting component 12 may comprise a mattress, mat, pad, cushion or virtually any other type of body supporting item. Component 12 is suitable for supporting humans as well as animals. Apparatus 10 is particularly adapted for indoor use although it may be used in a wide variety of indoor and outdoor applications. For example, the body supporting component 12 may be used in conjunction with a piece of furniture or it may serve as a floatation device for a pool. Component 12 may have assorted sizes and shapes. For example, component 12 may be rectangular as shown. Alternatively, it may include various non-rectangular configurations. The support component may have a size and thickness such that is suitable for use as a mattress, sofa bed or chair cushion, an exercise mat or a pet cushion. Representative dimensions for the body supporting components, when it is used as a mattress, are described in copending application Ser. No. 09/800,752, the disclosure which is incorporated herein by reference.

[0031] As shown in FIGS. 1-3, a body supporting component 12 comprises an internal foam core 14. Core 14 preferably features a self-inflatable, resilient open-celled foam composed of polyurethane or a similar material. The core is capable of being alternately filled with or exhausted of air, as required, such that the core is pressure adjustable. Preferably, a low density foam is employed, which exhibits a density of 1.2-2.5 pounds per cubic foot and an indention force deflection (IFD) of 22-45 when the foam is in a fully inflated state. In certain embodiments, such as shown in FIGS. 2 and 3, foam core 14 may include a plurality of pieces such as generally planar upper and lower segments 14 a and 14 b, which are preferably interlocked in some other suitable manner. In such versions, the respective pieces 14 a and 14 b preferably have different densities and IFD ratings. This permits the user to provide component 12 with at least two different comfort, body support levels. In alternative embodiments separate foam core segments having different densities and IFD ratings may be arranged laterally side-by-side within component 12. Various numbers of foam segments having assorted densities may be employed within the scope of this invention. This allows the user to change the firmness and density of the supporting surface, for example, by simply reversing or turning over the support component to expose a surface having a different density. This is particularly useful in situations where the component is employed as a mattress.

[0032] Core 14 is enclosed by a flexible sheet-like exterior covering 16, FIGS. 1 and 3. This covering should comprise a durable, airtight and preferably waterproof material such as nylon PVC or nylon polyurethane. Covering 16 may be constructed in a single piece or multiple pieces that are interconnected by sewing or RF welding. The latter technique is especially preferred because it renders the support component essentially airtight and watertight. This permits component 12 to be used as a float.

[0033] One or more valves are employed by component 12 for the purpose of selectively collapsing (deflating) and expanding (inflating) the foam core. As shown in FIGS. 1-3, an air passageway 18 is formed through outer covering 16 in pneumatic communication with the interior of component 12 and foam core 14. Air passageway 18 comprises a T-pipe 19 composed of PVC or some other type of durable plastic. The passageway includes a first tubular section 20 that extends outwardly through the covering. A second tubular section 24 is attached communicably and perpendicularly to section 18 at the interior end thereof. Tubular section 24 is arranged within component 12 and adjacent to the edge of foam core 14. Section 24 includes openings 25 and 26 formed at opposite ends of the tube section. The entire T-pipe is typically comprises a unitary piece although multiple interconnected segments may be used. Section 24 may be attached to section 20 at other than a perpendicular angle. A pair of upper and lower baffles 28 and 30 are mounted above and below T-pipe 19 adjacent the ends of foam core 14. These baffles comprise foam blocks that are relatively rigid compared to the self-inflating foam of core 14. They help to keep covering 12 separated sufficiently from core 14 so that the covering is not sucked into the T-pipe passageway 19 during deflation of component 12.

[0034] Tubular section 20 carries a plastic valve 21. The valve includes a peripheral flange 22 that engages the inside surface of covering 16. The flange is secured to the covering by RF welding or other means. In FIG. 3 a gap is depicted between the flange and the covering for clarity. A cap or closure 23, may be selectively and sealably interengaged with valve 21 to close the valve. Closure 23 and valve 21 may include complementary circumferential threads that are interengaged to close the valve. Cap 23 is selectively disengaged from tubular valve 21 to open the valve. It should be understood that a variety of known pneumatic valves may be employed within the scope of this invention including drain valves as described in copending U.S. patent application Ser. No. 09/800,752. The valve may also comprise assorted pressure relief valves and spring loaded check valves such as the boat valve manufactured by Halkey-Roberts. Such valves are currently employed in watercraft such as the Zodiac™.

[0035] The distal openings 25 and 26 of tubular section 24 are adjacent but face perpendicularly to foam core 14. The air passageway is spaced sufficiently close to the foam core and is within the airtight covering 12 such that the air passageway and valve 21 carried thereby communicate pneumatically with the open-celled foam core. When the core is squeezed, air from the cells in the core is exhausted through the open valve. Alternatively, when the core is in a collapsed condition, opening the valve (e.g. removing cap 23) causes the air to be drawn inwardly through the open valve and absorbed by the foam core. This causes component 12 to inflate. When cap 23 is engaged with valve 21, the valve is closed so that air is blocked from passing through passageway 18. If the mattress is partially or fully deflated, a closed valve prevents the foam from re-inflating. Alternatively, if the foam is already fully inflated, closing the valve allows a person or animal to engage component 12 without deflating the foam core.

[0036] Component 12 is depicted in a fully expanded or inflated condition in FIG. 1. In this state, the foam core has absorbed air and the cells of the foam are in their normal, fully inflated condition. As a result, the foam exhibits a low density and, when the valve is closed, the core provides a relatively firm support. Component 12 may be used in the fully inflated condition by simply closing valve 21 so that air is retained in the foam core.

[0037] To adjust the firmness and support of the body supporting component, cap 23 is removed and vacuum assembly 13 is operably interengaged with valve 21. The vacuum assembly comprises a standard vacuum pump 13, which may be a conventional household vacuum pump or an alternative type of vacuum means. A hose 34 having a suction inlet or nozzle 36 is operably attached to pump 13. To deflate and adjust the air pressure of foam core 14, nozzle 36 is fit over valve 21 by engaging the nozzle about tubular section 18 such that the distal end of the inlet or nozzle sealably engages the side surface of covering. The operator activates vacuum pump 13, which causes nozzle 36 to seal against the side 56 of component 12. The vacuum draws air from foam core 14 outwardly through the open valve. As air is drawn outwardly from the foam core in the manner indicated by arrow 40 in FIGS. 1 and 3, the cellular structure of the foam core is modified. The density of the core increases while the IDF (firmness) of the foam decreases. Eventually, foam core achieves a viscoelastic feel wherein a relatively high density of at least 3 lbs/ft³ and a relatively low indention force deflection value of below 15 are exhibited. As shown in FIG. 4, when component 12 achieves the foregoing parameters, it conforms to the bodily contour of a user and exhibits a supportive, and yet very soft foam resistance. The product exhibits slow recovery to application of an external pressure, which is a feature exhibited by viscoelastic foam products. The improved support and comfort achieved by component 12 are comparable to the levels provided by viscoelastic supports that are currently available, yet these benefits are achieved in the present invention by using a low density foam that is much less expensive and lighter weight than the standard viscoelastic materials. Moreover, unlike standard viscoelastic foam, component 12 may be pressure adjusted to the degree required to provide comfort and support levels desired by the user. Even after user U is engaged with component 12, the density and firmness levels may be fine tuned by pumping additional air outwardly from the foam core or, alternatively, by removing the vacuum pump 13 and hose 34 and permitting additional air to be drawn inwardly through the open valve and into the self-inflating foam core.

[0038] Component 12 may be fully collapsed by continuing to pump air out of the foam core until core 14 is fully deflated. The support component is now in a substantially flat and easy to manipulate condition. After the foam core is fully deflated, the user disengages nozzle 36 from valve stem 20 and promptly shuts the valve by attaching cap 23 to stem 20. This prevents the foam core from re-inflating. The user then wraps, folds or rolls up the deflated support component in the manner as shown in U.S. patent application Ser. No. 09/800,752. As further described therein, the support component 12 may carry a strap that encircles the rolled component to provide for convenient transportation and storage.

[0039] An alternative air passageway 18 a and valve 21 a are depicted in FIGS. 5 and 6. The air passageway includes a very short or abbreviated tubular port 20 a that is engaged with an opening in the covering (not shown) in a manner much the same as in the prior embodiment. A transverse, generally tubular element 24 a is attached unitarily to port 20 a. Once again, the air passageway may comprise a PVC T-pipe or similar component. A longitudinal slot 95 a is formed in tubular segment 24 a. This slot abuts and engages the edge of foam component 14 a. In this version, the baffles employed in the previously described embodiment are eliminated.

[0040] Valve 21 a comprises a standard pressure relief valve such as the boat valve manufactured by Halkey-Roberts. Valve 21 a is received by and secured within port 20 a such that the distal end 96 a of valve 21 a and an enclosed spring biased air injection needle 97 a (FIG. 5) are exposed exteriorly of the covering. The inner end 98 a of valve 21 a is open. A plurality of orifices 99 a are formed about the tubular inner end of the valve within passageway 18 a. As a result, the valve communicates pneumatically with the interior of the passageway and, therefore, with foam core 14 a.

[0041] Air is introduced into and removed from the foam core in a manner analogous to the previously described embodiment. Specifically, the vacuum hose fitting 36 a is engaged with valve 21 a such that spring biased air injection needle 97 a is resiliently opened, which opens valve 21 a. The vacuum pump is operated to draw air outwardly through the valve from the foam core. As a result, the pressure within the foam core is adjusted to provide a viscoelastic feel within the support component. When the desired levels of density and firmness are achieved, the vacuum hose fitting 36 a is disengaged from valve 21 a. The spring biased air injection needle returns to its normal position, which closes the pressure relief valve 21 a. As a result, the foam core is maintained in the selected pressure adjusted condition. To fully re-inflate the foam core, the user simply depresses the needle 97 a to re-open the valve. This permits the foam core to draw air inwardly through the valve and air passageway 18 a until the core re-inflates. Because the foam core employs a low density foam exhibiting a high level of air flow, the foam re-inflates rather quickly. A conventional cap or closure (not shown) may be attached to the valve when the valve is not in use. In the remaining figures shown herein, the valve is depicted in somewhat simplified form. However, it should be understood that the pressure relief valve shown in FIGS. 5 and 6, as well as other standard pneumatic valves, may be employed in each of the disclosed embodiments.

[0042] In the alternative version shown in FIG. 7, foam core 114 is again enclosed by an airtight covering 116. Air passageway 18 comprises a valve 121 that extends through and exteriorly of covering 116. The tubular valve 121 includes a peripheral flange 122 at its inner end. Flange 122 is heat welded to an interior surface of covering 116 such that the valve is permanently secured to the covering. A plastic air passageway comprising a T-pipe apparatus 119 is interengaged with valve 121. T-pipe 119 includes a tubular segment 120 that is inserted through the valve. The T-pipe also includes a second tubular segment 124 that is connected communicably and perpendicularly to segment 120. Segment 120 has an open distal end and segment 124 has opposing distal ends 125, 126 that are open so that the T-pipe provides an air passageway from the open valve into the interior of support component 112.

[0043] In this embodiment, a pair of relatively rigid foam blocks 128 and 130 are interposed between the edge of foam block 114 and the end of covering 116. Each block is spaced laterally apart from a respective open end 126 and 126 of T-pipe 119. These blocks serve as baffles and prevent the covering 116 from being sucked into the T-pipe when a vacuum is drawn on the foam core. It should be noted that the passageway shown in FIGS. 5 and 6 may also be used in this version.

[0044] In this embodiment, an exterior vacuum pump 113 includes a hose 134 and an end fitting 136 that is received within the opening of valve 122. The distal edge of fitting 136 engages the distal end of tubular segment 120 of T-pipe 119.

[0045] Cap 123 selectively and sealably engages and closes valve 122. When the cap is disengaged from the valve, self-inflating foam core 114 draws ambient air inwardly through the valve and T-pipe 119. Such air is absorbed by the foam core, which causes the core to inflate. If cap 123 is then sealably engaged with valve 122, the foam core is maintained in a fully inflated condition and the foam exhibits a low density and relatively high IDF.

[0046] To adjust the density of the foam core such that is simulates and feels like a viscoelastic product, cap 123 is removed from valve 121 and fitting 136 of vacuum pump 113 is inserted into the open end of the valve. The distal end of fitting 136 engages the distal end of tubular segment 120. Vacuum pump 113 is connected to an appropriate electrical outlet and activated so that air is sucked into the vacuum from foam core 114. Specifically, the air is transmitted, as shown by arrows 170, from the foam core, through the T-pipe and valve, and into vacuum 113. Sufficient air is drawn from the foam core to achieve a simulated viscoelastic effect in the foam core. The cellular structure of the foam is modified (constricted) to produce a high density, low IDF structure. When the desired firmness and support are achieved, fitting 136 is disengaged from valve 122. Cap 123 is sealably replaced onto the valve. The selected level of density and firmness are thereby maintained.

[0047] FIGS. 8-11 depict alternative versions of the pressure adjustable foam support featuring different types of vacuum pumps. For example, in FIG. 8, pump 213 is attached by a strap or pouch 280 carried on the side of the covering 216 of support component 212. A hose 234 is permanently connected to a valve 222 which extends outwardly from the support component through covering 216 in the manner similar to that previously described. Once again, valve 222 is in pneumatic communication with the low density polyurethane foam contained within support component 212. Although not shown, this embodiment may also include a T-pipe air passageway and baffles as previously described. A two-way switch valve 282 is disposed within hose 234.

[0048] In operation, vacuum pump 213 is operated when needed to deflate the foam core and adjust the air pressure in the core. When the vacuum pump is activated, air is drawn outwardly from the foam core through valve 222 and hose 234. That air is discharged as indicated by arrow 284. During this operation, switch valve 282 is maintained in an open condition so that air passes freely through the hose. When the desired level of density and firmness is achieved in the support component, the vacuum is deactivated and switch 282 is closed so that the level of air pressure that has been obtained in the foam core is maintained during use of the body supporting member 212. If the user needs to re-inflate the foam core or to otherwise add air into the core, he or she simply opens valve 282 so that air is allowed to re-enter the support member 212 through valve 222. That air is absorbed by the self-inflating foam such that density is reduced and firmness is increased.

[0049] In FIG. 9, body supporting member 312 is provided with a vacuum 313 that is secured to the body supporting member by a pouch or strap 380 similar to that in the previously described embodiment. In this version, hose 334 is releasably attached to valve 322 in a manner such as described in connection with FIG. 1-7. Pressure is adjusted within the foam core by selectively engaging the vacuum fitting 336 with valve 322 and activating pump 313. Alternatively, the pump fitting can be disengaged from the valve to allow the self-inflating foam core to drawn air inwardly through valve 322. In either case, when the desired pressure level is achieved, cap 323 is re-engaged with valve 322 to maintain the selected degree of density and firmness.

[0050] In FIG. 10, support component 412 again includes a covering 416 and an enclosed foam core 414. A vacuum 413 is carried in an external pouch 480 carried by covering 416. A flexible tube 434 is connected to vacuum to 413. Tube 434 carries a fitting 436 that engages a valve 422 extending through and exteriorly of covering 416. As in the prior versions, valve 422 includes an interior flange that is heat welded to the inside surface of the covering. A T-pipe 419 is interengaged with valve 422, again in the manner shown in FIG. 5. Fitting 436 exteriorly engages valve 422 in this version. The fitting may be permanently or releasably attached to the valve. Foam baffle blocks 428 and 430 are disposed between foam core 413 and covering 416 and are spaced apart from the transverse openings of T-pipe 419.

[0051] Vacuum pump 413 is connected to an electrical power source and is activated, such as by a remote control module 490 to selectively pump air out of core 414 in the manner previously described. Once again, a two-way valve 482 is disposed in the hose. This valve is open during the vacuum operation and is closed to maintain the foam core at a selected air pressure. Subsequently, valve 482 is opened to re-introduce air into the self-inflating foam when needed. It should also be noted that in each of the previous described embodiments, the vacuum pump may be provided with a standard blower that expels air. The vacuum hose may be communicably attached to the blower with the valve opened and the hose engaged with the support component, as described above. The vacuum pump is then operated to pump air through the open valve into the foam core. Air pressure within the core is increased accordingly until it achieves a desired level of comfort and firmness.

[0052] In FIG. 11, support component 512 is constructed in a manner similar to the previously described embodiments. In particular, foam core 514 is enclosed within airtight covering 516. In this version, a vacuum 513 is also enclosed within covering 516 at one end of core 514. Vacuum 513 is communicably connected to a valve 522 that extends outwardly through the covering. The valve may be secured to the covering by a flange as previously described, which holds the covering apart from the vacuum. This again prevents the covering from being sucked into the vacuum during operation. An electrical cord and on/off switch are connected to the interior vacuum through an airtight flange 594 formed in covering 516.

[0053] When pump 513 is activated, it operates to pump air from core 514 outwardly through attached valve 522. Once again, a cap, not shown, may be employed to sealably close the valve and maintain the selected air pressure within core 514. The pump remains in an off condition when the valve is closed. Subsequently, the valve may be opened to re-introduce air into the self-inflating foam when needed.

[0054] As previously stated, the support apparatus of this invention may be used in a wide variety of mattresses, pads, cushions, mats, etc. When the invention is employed in a mattress, a supporting frame is typically disposed beneath the mattress for the support thereof. This frame may comprise a fixed structure composed of wood, metal, etc. Alternatively, it may comprise an adjustable structure. In certain embodiments, the supporting frame may include an adjustable air bladder that is provided with its own air inlet/exhaust valve, which enables the mattress supporting frame to be raised and lowered as required.

[0055] The pump may be mounted in various locations. In addition to the locations described above, the pump may be carried in a pouch formed in a mattress cover that is releasably engaged over the support component. The mattress cover may be provided with an opening that communicates with and receives the valve.

[0056] In one version of this invention, air pressure may be continuously and alternately added to and removed from the foam core. Such an operation is particularly effective for use in a hospital mattress designed to combat bed sores. The hospital mattress may be constructed largely in the manner shown in FIG. 8. The vacuum pump shown therein is replaced by a diaphragm or other type of pump designed to selectively introduce air into or remove air from the foam core. A hose is permanently interconnected between the pump and an air passageway that pneumatically communicates with the interior of the support component and the foam core therein. The valve shown in FIG. 8 is eliminated from the hose. The pump is operated to alternately and continuously pump air into and suck air out of the foam core. The movement of air is extremely slow (i.e. it would take several hours to completely deflate the foam core). Every several minutes, the operation changes from inflation to deflation and vice versa. This continuous adjustment of air within the foam core and the mattress helps to prevent ulcers from forming on the patient's skin. Multiple valves may be formed in the mattress and each may be communicable connected with a respective vacuum such that different air pressures are exhibited at different locations in the mattress. This continuous pressure adjustability helps to prevent the formation of ulcers and bed sores on the patient's skin.

[0057] It should be understood various other arrangements may be employed within the scope of this invention which include one or more of the features from the respective embodiments shown herein. In certain versions, multiple valves may be utilized. In all versions it is important that the support component be pressure adjustable in accordance with the teaching of this invention so that the foam core feels like a viscoelastic slow recovery foam. This is achieved with much less expense and using a much lighter weight, low density foam. Furthermore, the foam employed in the present invention is adjustable unlike standard viscoelastic foam so that individually desired levels of firmness, comfort and support may be achieved.

[0058] From the foregoing it may be seen that the apparatus of this invention provides for a pressure adjustable foam support apparatus and to a method of producing a body supporting structure with adjustable levels of density and firmness simulating those of viscoelastic foam. While this detailed description has set forth particularly preferred embodiments of the apparatus of this invention, numerous modifications and variations of the structure of this invention, all within the scope of the invention, will readily occur to those skilled in the art. Accordingly, it is understood that this description is illustrative only of the principles of the invention and is not limitative thereof.

[0059] Although specific features of the invention are shown in some of the drawings and not others, this is for convenience only, as each feature may be combined with any and all of the other features in accordance with this invention.

[0060] Other embodiments will occur to those skilled in the art and are within the following claims: 

What is claimed is:
 1. A pressure adjustable foam support apparatus comprising: a resilient, air pressure adjustable, self-inflating foam core; a flexible airtight covering that encloses said core; an air passageway formed through said covering in pneumatic communication with said foam core, which passageway carries a valve for alternately permitting and blocking passage of air into and out of said core through said passageway, said valve being opened to exhaust air from and at least partially collapse said core and to allow a core that is at least partially collapsed to draw in air through said passageway and expand, said valve being selectively closed with said core in one of a plurality of fully inflated and partially collapsed states to maintain a selected air pressure within said core, whereby corresponding levels of density and firmness are exhibited by said core, at least one such level of density and firmness providing said core with a viscoelastic feel.
 2. The apparatus of claim 1 further including a vacuum pump communicably engagable with said passageway such that opening said valve and operating said vacuum pump exhausts air from said foam core through said passageway to at least partially collapse said core.
 3. The apparatus of claim 1 in which said foam core has a density of 1.2-2.5 pounds per cubic foot and an indention force deflection value of 22-45 in a fully inflated condition.
 4. The apparatus of claim 1 in which said core includes a normal cellular structure in a fully inflated condition and a modified cellular structure in said partially collapsed condition, which modified cellular structure is caused by a reduction in air pressure in said core.
 5. The apparatus of claim 1 in which said passageway includes a first pipe portion disposed within said covering and a second pipe portion attached communicably and extending transversely to said first pipe portion, said second pipe portion extending through and being pneumatically communicable with air exteriorly of said covering.
 6. The apparatus of claim 1 further including a baffle disposed adjacent said passageway intermediate said foam core and said cover to restrict said cover from being sucked into said passageway by operation of said vacuum pump.
 7. The apparatus of claim 1 in which said foam core includes at least two interengaged foam components disposed within said covering.
 8. The apparatus of claim 7 in which each said foam component includes a respective density and indention force deflection (IFD) that is different from that of the other said foam component.
 9. The apparatus of claim 1 in which said foam core includes polyurethane foam.
 10. The apparatus of claim 2 in which said vacuum pump is attached to said passageway exteriorly of said covering.
 11. The apparatus of claim 2 in which said vacuum pump is attached to said passageway interiorly of said covering.
 12. The apparatus of claim 1 in which said core is collapsible such that it includes density of at least 3 lbs/ft³ and an indention deflection force valve of less than
 15. 13. The apparatus of claim 3 in which said core is collapsible such that it includes density of at least 3 lbs/ft³ and an indention deflection force valve of less than
 15. 14. A method of producing a body supporting apparatus, which apparatus includes selected levels of density and firmness, said method comprising: providing a resilient, air pressure adjustable, self-inflating foam core; enclosing said foam core in a flexible airtight covering; providing an air passageway through said covering and in pneumatic communication with said foam core, which passageway carries a valve for alternately permitting and blocking the passage of air into and out of said core through said passageway; opening said valve and selectively exhausting air from said core and introducing air into said core through said passageway to adjust the air pressure within said core until said core achieves selected levels of density and firmness; and closing said valve to maintain said core at said selected levels of density and firmness.
 15. The method of claim 1 in which air is exhausted from said core by opening said valve and by pumping air from said core outwardly through said passageway.
 16. The method of claim 1 wherein selectively exhausting and introducing air modifies the cellular structure of said foam to achieve the selected levels of density and firmness.
 17. The method of claim 1 in which said foam core has a density of 1.2-2.5 pounds per cubic foot and an indention force deflection value of 22-45 in a fully inflated condition.
 18. The method of claim 17 further including adjusting the air pressure in said core until a density of at least 3 lbs/ft³ and an indention force deflection valve of below 15 are achieved.
 19. A pressure adjustable foam support apparatus comprising: resilient, air pressure adjustable, self-inflating foam core; a flexible, airtight covering that encloses said core; an air passageway formed through and covering in pneumatic communication with said foam core; and a pump communicably engagable with said passageway for selectively introducing air into said core and exhausting air from said core through said passageway to adjust the air pressure within said core, the pressure within said foam core being adjustable to provide said foam core with a viscoelastic feel. 